Dev tools · alternatives · 2026

24 alternatives to Domain WHOIS API

Free domain lookup — RDAP, no API key needed

Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Prices are shown for the 1 we have checked on their own sites, 1 of them free or with a free tier.

1. 1
   DomainDetails.com - Free & Private WHOIS▲26

   Free & Private domain research - right in your browser

   Dec 2025 · domaindetails.com · its alternatives →

2. 2
   WHOIS by Weekend Labs▲67

   Unlock the secrets of any domain with just one WHOIS search

   2023 · its alternatives →

3. 3
   takenorfree.com▲6

   Domain availability checks for humans and AI agents.

   Jun 2026 · takenorfree.com · its alternatives →

4. 4
   WHOIS Checker - Chrome Extension▲10

   Check WHOIS details of any website with a single click.

   2024 · hostingchecker.net · its alternatives →

5. 5
   DomainWatch▲352

   Domain Monitoring Made Easy

   2018 · webmaster.ninja · its alternatives →

6. 6
   Whois³▲80

   Know about everyone in web3

   2022 · its alternatives →

7. 7
   Domainduck▲5

   A domain API for pricing, WHOIS, availability and more.

   Jan 2026 · domainduck.io · its alternatives →

8. 8
   Whois▲6

   Whois : domain and IP address Lookup. All TLDs

   2019 · its alternatives →

9. 9
   WhoisJSON▲1

   WhoisJSON — WHOIS, DNS & SSL in one API key. Free plan.

   Mar 2026 · whoisjson.com · its alternatives →

10. 10
    WHS.IS▲37

    Whois lookup and API

    2024 · whs.is · its alternatives →

11. 11
    API Portfolio — 5 Free APIs▲8

    5 free dev APIs: WHOIS, Company, Email, Geo, Sanctions

    Jul 2026 · on13uka.github.io · its alternatives →

12. 12
    NS6.com▲71

    Register domains across 800+ extensions with free WHOIS privacy, free DNS and free SSL on every domain. Search, transfer in, and manage everything in one place.

    2022 · ns6.com · its alternatives →

13. 13
    Quick Whois Lookup for Domains▲5

    Get detailed domain information quickly and easily

    2023 · its alternatives →

14. 14
    Notify.domainsfree tier, from $2/mo▲322

    Know the moment a domain opportunity appears

    Aug 2026 · notify.domains · its alternatives →

15. 15
    Free Domain Tool▲14

    Domain availability checker

    2025 · domainaide.com · its alternatives →

16. 16
    digga – DNS, RDAP/WHOIS, subdomains and more in one lookup▲6

    Free domain lookup for DNS records, RDAP, WHOIS, subdomains, IPs, and email security. Research any domain in one fast report.

    Jul 2026 · digga.dev · its alternatives →

17. 17
    Website Setup Tools▲6

    Free Domain Name Generator, WHOIS Information, IP Lookup

    2021 · websitesetuptools.com · its alternatives →

18. 18
    Ip Number Lookup▲12

    Free ip number lookup online tool!

    2024 · its alternatives →

19. 19
    WHOIS_OS▲6

    Domain, nameserver lookup & IP tools

    2023 · whoisos.com · its alternatives →

20. 20
    tldx▲109

    Fast CLI to bulk-check domains via RDAP & MCP

    May 2026 · github.com · its alternatives →

21. 21
    Whoisology▲106

    Find Connections Between Domain Names & Their Owners

    2014 · whoisology.com · its alternatives →

22. 22
    Registered Domain Names Search▲22

    Access our comprehensive domain database through a powerful API. Check domain availability and status with simple HTTP requests.

    2017 · domainsdb.info · its alternatives →

23. 23IC
    I crossed a thesaurus with a domain availability checking API▲113

    2013 · domainmasher.com · its alternatives →

24. 24
    DomainBrief - domain lookup report▲4

    Look up any domain and get a shareable report

    Jun 2026 · domainbrief.app · its alternatives →

Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →